Charge-Transfer Complex Formation between Stilbenes and 7,7,8,8-Tetracyanoquinodimethane

摘要

Formation of intermolecular charg-transfer complexes between 7,7,8,8-tetracyanoquinodimethane (TCNQ) and two different series of stilbene derivatives has been studied spectroscopically at 25∩ in 1,2-dichloroethane. The compounds of Series グ include stilbene and derivatives which have fused phenyl rings on one end of the central ethylene structure and a phenyl ring on the other end. The other Series, ケ, is comprised of stilbenes which have various para substituents on one of the two phenyl rings. The equilibrium constant, KcAD and the molar extinction coefficient, ュルAD, were determined using the Scott equation. The values of the charge-transfer transition frequency, ロAD and KcAD correlated well respectively with the ionization potentials of the fused rings of Series グ or of the compounds of Series ケ and with the values of ヲp, the Hammett constants of the Series ケ substituents. trans-4-N,N-Dimethylaminostilbene and trans-4-nitrostilbene were found to be able to participate in electron transfer reaction with TCNQ forming the corresponding anion radical, TCNQ-: